Muted inflation and the sudden drop in oil prices will help shape the Federal Open Market Committee’s decision on when to boost interest rates. The dangers of falling commodities prices.

Never write a letter and never destroy one. “That eternally sage counsel came from the famed Cardinal Richelieu, who served as Louis XIII’s brain. Were the wily prelate alive today, we’ve not a scintilla of a doubt he would have amended his exhortation to replace ‘letter’ by ‘e-mail.’ But, of course, the advice, if anything, is even more pungent now than it was then.”

As constant readers might recognize, that suggestion comes from my illustrious predecessor in this space, the late and much-missed Alan Abelson. Yet, some 9½...